<template>
<div class="city_body">
    <div class="city_list" ref='box'>
        <div class="city_hot">
            <h2>热门城市</h2>
            <ul class="clearfix">
                <li v-for='city in hot' :key='city.id'
                @click='handlerToCity(city.name,city.id)'
                >{{city.name}}</li>
            </ul>
        </div>
        <div class="city_sort">
            <div v-for='cityGroup in cities' :key='cityGroup.index'>
                <h2 ref='h2'>{{cityGroup.index}}</h2>
                <ul>
                    <li v-for='city in cityGroup.list' :key='city.id'
                        @click='handlerToCity(city.name,city.id)'
                    >
                        {{city.name}}
                    </li>
                </ul>
            </div>
        </div>
    </div>
    <div class="city_index">
        <ul>
            <li 
                v-for='(cityGroup,index) in cities' 
                :key='cityGroup.index'
                @click='goToCity(index)'
                :class='{active:index===activeIndex}'
            >
                {{cityGroup.index}}
            </li>
        </ul>
    </div>
</div>
</template>

<script>
export default {
    name:'City',
    data(){
        return {
            hot:[],
            cities:[],
            // 当前被点击的字母的索引
            activeIndex:-1
        }
    },
    async created(){
        // 一个国家城市信息基本是固定不变的
        // 有本地存储信息，就直接从本地获取
        let hot = window.localStorage.getItem('hot');
        let cities = window.localStorage.getItem('cities');
        if(hot&&cities){
            this.hot = JSON.parse(hot);
            this.cities = JSON.parse(cities);
            return;
        }


        // 第一次
        // 请求城市数据
        let data = await this.$axios.get('/api/city');
        // 请求到信息以后存储到本地存储
        window.localStorage.setItem('hot',JSON.stringify(data.data.hot))
        window.localStorage.setItem('cities',JSON.stringify(data.data.cities));

        this.hot = data.data.hot;
        this.cities = data.data.cities;
    },
    methods:{
        // 点击字母跳转到对应城市组
        goToCity(index){
            // console.log(index)
            this.activeIndex = index;
            this.$refs.box.scrollTop = this.$refs.h2[index].offsetTop
        },
        // 点击城市修改vuex里面的数据，并跳转nowplaying
        handlerToCity(nm,id){
            // 修改vuex里面的数据
            this.$store.commit('city/CITY_INFO',{
                nm,
                id
            })
            // 点击跳转nowplaying
            this.$router.push('/movie/nowplaying')
        }
    }
}
</script>

<style scoped>
#content .city_body{ margin-top: 45px; display: flex; width:100%; position: absolute; top: 0; bottom: 0;}
.city_body .city_list{ flex:1; overflow: auto; background: #FFF5F0;}
.city_body .city_list::-webkit-scrollbar{
    background-color:transparent;
    width:0;
}
.city_body .city_hot{ margin-top: 20px;}
.city_body .city_hot h2{ padding-left: 15px; line-height: 30px; font-size: 14px; background:#F0F0F0; font-weight: normal;}
.city_body .city_hot ul li{ float: left; background: #fff; width: 29%; height: 33px; margin-top: 15px; margin-left: 3%; padding: 0 4px; border: 1px solid #e6e6e6; border-radius: 3px; line-height: 33px; text-align: center; box-sizing: border-box;}
.city_body .city_sort div{ margin-top: 20px;}
.city_body .city_sort h2{ padding-left: 15px; line-height: 30px; font-size: 14px; background:#F0F0F0; font-weight: normal;}
.city_body .city_sort ul{ padding-left: 10px; margin-top: 10px;}
.city_body .city_sort ul li{ line-height: 30px; line-height: 30px;}
.city_body .city_index{ width:20px; display: flex; flex-direction:column; justify-content:center; text-align: center; border-left:1px #e6e6e6 solid;}
.city_body .city_index ul li.active{
    color:white;
    background:#e54847;
}
</style>